1. Field of the Invention
This invention relates to masonry construction of openings, such as doorways, windows, and the like.
More particularly, the present invention relates to the formation of the lintels of openings, such as doorways, windows, etc., in masonry construction.
In a further and more specific aspect, the instant invention concerns a box lintel and the use of the box lintel in masonry construction.
2. Prior Art
In the prior art, the construction of openings, such as doorways, windows, and the like, in masonry block walls is generally accomplished by forming the wall to approximately the desired height of the opening while defining the sides of the opening with upright lintel supports formed of the masonry blocks. An elongated flat piece of metal is placed between the supports to span the opening. Courses of masonry blocks are then placed on the metal piece and the wall is completed. The problem is that all of the weight of the masonry blocks above the lintel are carried by the metal piece. Therefore, the maximum allowable length of the metal piece and, consequently, the size of the opening, is severely limited. Even with the limitations of size, the metal piece must be extremely rugged and heavy.
In some prior art construction, the entire opening, including the sides and in some instances the threshold, is constructed utilizing a preformed steel frame. One problem with this preformed steel frame is that it can only be purchased in predetermined sizes. Further, the preformed steel frame is extremely heavy and cumbersome to work with. Finally, the appearance of the preformed steel frame is not esthetically pleasing in most instances.
It would be highly advantageous, therefore, to remedy the foregoing and other deficiencies inherent in the prior art.
Accordingly, it is an object of the present invention to provide an improved lintel for openings in masonry walls.
Another object of the present invention is to provide a box lintel which can be easily cut and formed to any desired size.
And another object of the present invention is to provide a box lintel that can be used to form substantially any reasonably sized opening in a masonry wall.
Still another object of the present invention is to provide a box lintel which is sturdier than prior art lintels.
Yet another object of the present invention is to provide a box lintel which is lighter and stronger than prior art lintels.
And still another object of the present invention is to provide a box lintel which is less expensive than prior art lintels.
A further object of the present invention is the provision of an improved method of forming openings in masonry walls using the box lintel.
Still a further object of the present invention is a method of forming openings in masonry walls with the box lintel, which method is simpler and provides a more rugged and esthetically pleasing opening.
And a further object of the present invention is a method of forming a box lintel for use in masonry walls.
Briefly, to achieve the desired objects of the instant invention, in accordance with a preferred embodiment thereof, a box lintel is first provided which includes an elongated, hollow metal form with a lower wall, integrally formed side walls extending upwardly therefrom, and integrally formed partial upper walls extending inwardly from the side walls. The lintel is constructed with a notch in the lower wall at either end for allowing grout/mortar to flow into a supporting column of bricks. The instant invention also includes a method of fabricating the box lintel, which includes the steps of providing an elongated flat sheet of metal and bending the flat sheet of metal into a hollow metal form with a lower wall, integrally formed side walls extending upwardly therefrom, and integrally formed partial upper walls extending inwardly from the side walls.
The form is adapted to be positioned on upright masonry supports so as to span an opening and to be filled with grout/mortar and to receive one or more courses of masonry bricks on the upper walls. In a preferred embodiment, the form has an upwardly directed camber formed therein. When partially hollow masonry blocks are used in conjunction with the form, the masonry blocks can also be filled with grout/mortar to increase the weight bearing capabilities. The upward camber being sufficient to deform the lintel to a flat surface when receiving grout/mortar with masonry bricks on the upper walls. Also, the strength of the lintel increases as more of the masonry blocks are filled with grout/mortar.